moby--moby/hack/make/.detect-daemon-osarch

#!/bin/bash
set -e

# Retrieve OS/ARCH of docker daemon, eg. linux/amd64
export DOCKER_ENGINE_OSARCH="$(docker version | awk '
	$1 == "Client:" { server = 0; next }
	$1 == "Server:" { server = 1; next }
	server && $1 == "OS/Arch:" { print $2 }
')"
export DOCKER_ENGINE_GOOS="${DOCKER_ENGINE_OSARCH%/*}"
export DOCKER_ENGINE_GOARCH="${DOCKER_ENGINE_OSARCH##*/}"

# and the client, just in case
export DOCKER_CLIENT_OSARCH="$(docker version | awk '
	$1 == "Client:" { client = 1; next }
	$1 == "Server:" { client = 0; next }
	client && $1 == "OS/Arch:" { print $2 }
')"